Do not test on nightly

Author: tknopp

.github/workflows/CI.yml

@@ -19,7 +19,6 @@ jobs:
       matrix:
         version:
           - '1' # Leave this line unchanged. '1' will automatically expand to the latest stable 1.x release of Julia.
-          - 'nightly'
         os:
           - ubuntu-latest
         arch: